This invention pertains to a food preparation device and more particularly to an oven for preparing foods such as pizza, pasta products, sandwiches, breakfast meats, cookies, breads, and other similar foods of relatively shallow thickness, and to apparatus for the freezing of foods.
Several types of ovens are available in the market for cooking foods, the two most popular types being the deck oven and the convection oven. In the deck oven, the food is placed within the oven on a shelf, under which a heat source is located for cooking the food. Several drawbacks exist with the deck oven, one of which is the requirement of having to manually load the unprepared food within the oven, and then manually unload the food after it has been cooked. The manual loading and unloading of the food does not allow for rapid food preparation during high peak periods. Another drawback associated with the deck oven is high energy consumption. Since the deck oven cooks primarily by heat conduction through the shelf, and not by convection, increased energy usage results from having to maintain the shelf area upon which the food is located at the required temperature in order to prepare the food. Furthermore, since the cooking is primarily by heat conduction, it is difficult to regulate the temperature within the deck oven in order to cook foods having different cooking temperatures and cooking times.
Convection ovens, unlike deck ovens, naturally cook by heat convection instead of heat conduction. Although convection ovens use less energy than deck ovens, they still require a disproportionate amount of energy in order to cook the food since additional energy is required to heat all of the air within the oven, which results in cooking by convection. Like the deck oven, the convection ovens also require manual loading and unloading of the food product within the oven, thereby preventing rapid preparation of food during high peak periods. Another drawback of the convection oven, similar to the deck oven, is that it is not easily adaptable to cook different foods having various cooking temperatures and cooking times. This results from the cooking by convection process, which requires all of the oven air to be either cooled below its present temperature or heated above its present temperature in order to meet the heating requirement of the particular food. Naturally, this repeated cooling and reheating process produces undesirable energy consumption.
Because of the aforementioned drawbacks of the deck and convection ovens, peak periods during which food delivery demands are highest can only be met by having several ovens available, each operated at a particular temperature for a particular type of food. Consequently, the drawbacks of each individual oven, for example, high energy consumption and manual operation, are magnified by the number of additional ovens required.
In those cooking ovens which recirculate air by means of an impeller and plenum assembly for reheating and subsequent use in the cooking process, several problems and disadvantages exist with these ovens. In the majority of these ovens, the impeller withdraws air from the cooking area and recirculates it over a heat source from which it is drawn and directed into a plenum for distribution to various duct devices, which direct the air to the product to be cooked. A prerequisite for an evenly cooked food product is the uniform distribution of reheated air by the impeller assembly through the plenum and duct devices. In order for the impeller assembly to radially and axially distribute heated air uniformly within the plenum for subsequent uniform distribution through the duct devices, the reheated air upstream of the impeller should follow a path to the impeller that is generally parallel to the longitudinal axis of the impeller and approximately two to three feet in length. This results in the reheated air being drawn by the impeller along a path substantially perpendicular to the impeller's plane, thereby permitting the impeller to uniformly distribute the reheated air through the plenum and to the duct devices. These ovens which utilize such an impeller and plenum assembly, and which provides a sufficiently long air flow path in front of the impeller, are longer in length than required and therefore take up needed space.
A further disadvantage of this increased length of the oven is that it requires the air to be heated to travel a longer distance to and through the heating air. This increased distance the air must travel causes the air to lose excess heat energy to its environment, which can only be remedied by increasing the heat source temperature. This, of course, is an undesired increase in energy consumption.
Attendant also with the increase in length of the oven is the problem with noise resulting from the reinforcement of reverberations of the moving parts located within the enlarged areas of the oven.
This application relates to certain improvements over the food preparation apparatus claimed in copending application Ser. No. 359,921, filed Mar. 19, 1982 in the name of Donald P. Smith and Virgil L. Archer. The finger support structure of FIGS. 10-13 is claimed in copending application Ser. No. 386,610, filed June 9, 1982, in the name of Daniel S. Kaminski.